Options Importer Extension allows you to import automatically custom field's options within a CSV file, also you can Delete all options in a custom field with only one click
Screenshot (click to enlarge)
Releases
Since CiviCRM 5.x, extension releases compatible with CiviCRM 5.0 are compatible with 5.0 and later. An extension release compatible with 5.25, for example, means that it requires CiviCRM 5.25 or later.